• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.10
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• pp.950-957
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• 2007

This paper considers acoustic characteristics of silencer within a dry vacuum pump. The main objective is to reduce noise in dry vacuum pump using the new designed silencer. First, SPL and sound intensity are measured for noise source identification and the new model silencer is designed corresponding to noise characteristics. 4-pole parameters are used to predict the transmission loss which is one of the interest characteristics of the new silencer. The calculated transmission loss is then used to change main effective factor and optimal value is selected by using design of experiment. By conducting an experiment, it is proved that the new designed silencer has reduced noise level by 6 dB(A) more than the original one.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.922-925
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• 2007

In the usual dry etching process for the TFT-LCD fabrication, it is hard to monitor the basic plasma parameters such as density and temperature. However, the basic parameters are easily monitored during the dry etching process. We have simultaneously measured the electric characteristics and basic plasma parameters of the dry etching chamber during the process, analyzed them to interpret plasma parameters. For the Ar plasma discharge case, we could obtain the density and temperature from the electric characteristics using a simple simple sheath model.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.249-251
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• 2001

A novel technology for recycling valuable metals contained in waste dry-battery by vacuum metallurgy was devised by theoretical analysis. On the condition of the total chamber pressure of 1.013$\upsilon$10$^1$Pa, Hg, Cd and Zn are distilled in the temperature range of 773~973K, Pb is volatilized in the range of 1173~1273K while Mn, Cu, Fe and C are remained in residual. MnO$_2$and ZnO are reduced by carbon in waste dry-battery in 773~1273K. Pure metals including Zn, Cd, Hg and Pb can be recovered respectively from their mixed vapor by fractional condensation. Metal Cu and MnO$_2$can be obtained from the residual by hydrometallguical method. The technology can eliminate the pollution of Cd, Hg and Pb to environment.

• Proceedings of the Korean Vacuum Society Conference
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• 2008.08a
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• pp.356-356
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• 2008

• Journal of agriculture & life science
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• v.45 no.1
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• pp.89-99
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• 2011

This study was carried out to investigate effect of irradiation doses on quality of vacuum-packed dry-cured ham during storage. Dry-cured pork slices were vacuum-packaged in nylon/ polyethylene bags. Vacuum-packed dry curd pork was stored at $10{^{\circ}C}$ for 12 weeks after irradiation (0 kGy, 2.5 kGy, 5 kGy, 7.5 kGy and 10 kGy) and physicochemical properties of dry curd porks, such as meat color surface, thiobarbituric aicd reactive substances, volatile basic nitrogen, pH, microbial (total plate count, Lactobacillus) and sensory properties (color, flavor, overall acceptability) were investigated. Irradiation treatment decreased a*-value, TPC and Lactobacillus. Irradiation dose significantly (p<0.05) increased irradiation flavor and TBA value. However, irradiation dose decreased redness and sensory color in dry-cured ham. The quality of dry-cured ham was affected by the irradiation dose. The results suggested that dry-cured ham irradiated at 5 kGy dose may show optimum quality characteristics of the products as well as microbial safety.

• Proceedings of the Korean Vacuum Society Conference
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• 1994.02a
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• pp.23-23
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• 1994

• Proceedings of the Korean Vacuum Society Conference
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• 1996.06a
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• pp.67-67
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• 1996

• Proceedings of the Korean Vacuum Society Conference
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• 1996.02a
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• pp.144-144
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• 1996

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.6
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• pp.121-128
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• 2019

There is a big move to build zero-energy buildings in the form of passive houses that reduce energy waste worldwide. Korea has set a goal of reducing its greenhouse gas emissions by 37% by 2030 through the activation of green buildings, such as strengthening the energy levels of new buildings and improving the energy efficiency of existing buildings. The use of insulation with high insulation performance is one of the key technologies to realize this, and vacuum insulation is the next generation insulation that blocks the energy flow of the building. In this study, we measured the bonding structure of dry and wet processing glass fiber core materials and compared the insulation performance of vacuum insulation panel. In addition, the insulation performance of vacuum insulation panel was measured according to the thickness of the laminated core. It can be confirmed that the lamination structure of the core and the lamination thickness are important factors for the heat insulating performance of the vacuum insulating panel.

• Food Science of Animal Resources
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• v.42 no.4
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• pp.639-654
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• 2022

The current study investigated the effects of the most suitable modified atmosphere packaging (MAP) on the physicochemical, microbiological, and sensory properties of fermented dry sausages during 45 days of refrigeration (4℃) storage period. Treatments were vacuum-packed (control), 25% CO₂/75% N₂ (MAP1), 50% CO₂/50% N₂ (MAP2), 70% CO₂/30% N₂ (MAP3), and 100% CO₂ (MAP4). All MAP samples regardless of their CO₂ composition significantly (p<0.05) decreased in pH, a_w, total plate count, and lactic acid bacteria count values as compared to the vacuum-package during storage. The Enterobacteriaceae count in all MAP packaging was significantly (p<0.05) lower than the vacuum-packed samples and counts in MAP3 and MAP4 samples were markedly (p<0.05) lower than all other treatments in prolonged storage of 15 and 45 days. Based on the thiobarbituric acid reactive substance content at day 15 and 30 storage time, treatments are ranked as follows: Vacuum-packed>MAP1>MAP2>MAP3>MAP4. The a^* of MAP4 was higher than all other treatments. In the final storage days, no variation was exhibited (p>0.05) among treatments in lactic acid aroma and sourness, and MAP2 samples had the lowest (p<0.05) overall acceptability. The use of MAPs with an increase in the CO₂ from MAP1 to MAP4 samples can help in better microbial inhibition than vacuum package, and 70% CO₂/30% N₂ (MAP3) and 100% CO₂ (MAP4) were effective to maintain several quality parameters (a_w, pH, microbial inhibition, stability against lipid oxidation, and instrumental color traits) and extend the shelf life of dry fermented sausage.